Our research is concerned with basic mechanisms of the regulation and control of cell growth, with particular reference to wound healing and neoplasia. The cornea is ideal for such studies because it is avascular and the different cell layers represent populations of isolated cells of different cell types. We have recently isolated and almost completely purified fractions of growth factors of biological origin which promote not only cell growth but inhibition of cell growth of various corneal cells. We have found that certain combinations of fractions of a mesodermal growth factor produce malignant-like transformations of corneal fibroblasts whereas other combinations of these fractions inhibit these transformations. These observations could be of the utmost importance in providing chemical tools for regulating cell growth. The mechanism of action of these growth stimulating factors is being studied both in organ cultures of whole rabbit corneas as well as in tissue cultures of corneal cells. A computerized image analysis system has been developed and used to evaluate and quantitate the growth responses of the corneal stromal cells to specific growth factors in organ culture. This computerized image analysis system also provides a method for the quantitation of the responses of connective tissue cells in wound repair and provides a means for evaluating the influence of different drugs on wound healing either in organ culture or in living animals.